[Expression of urokiase-type plasminogen activator and matrix metalloproteinases in human tissue of abdominal aortic aneurysm].

Abstract

Objective: To explore the expression of urokinase-type plasminogen activator (u-PA) and matrix metalloproteinases in human abdominal aortic aneurysm (AAA) tissue.

Methods: Immunohistochemistry and in situ hybridization were employed to detect the protein and mRNA expression of u-PA, gelatinase A (MMP-2) and gelatinase B (MMP-9) in the tissue sections of 30 AAA specimens and 30 normal human abdominal aorta specimens.

Results: The expressions of u-PA and MMP-9 were mainly found in the macrophages in AAA tissue, but not in normal human abdominal aorta tissues. The expression of MMP-2 was found mainly in the smooth muscle cells in AAA tissues, but not in normal human abdominal aorta tissues.

Conclusion: u-PA produced by macrophages may immediately activate proMMP-2 and proMMP-9, which play a pivotal role in the formation and development of AAA.